16 hours for stadium upgrades instead of 18?

Hey guys. Just a suggestion for stadium upgrades, I believe it should be 16 hours instead of 18, so we as players can manage our time to train players and upgrade stadiums at the same time. I just find it hard to keep on top of everything with this two-hour gap. Personally, I would find it much easier if training and upgrades finished together (2 trainings = 16 hours, 1 upgrade = 16 hours). What do you guys think?